Comments by "flagmichael" (@flagmichael) on "What is the best Toyota Hybrid Battery? Li-Ion or NiMH" video.

  1. This is a subject I am very familiar with. I would be very surprised if it does. (A plate doesn't do it; stopping EMFs requires an RF shield. RF and EMF are names for the same phenomenon: electromagnetic energy.) The EMF story goes back to 1984, the year I started working in an electric utility. Data mining on a survey found that the electrical workers in the sample had roughly twice the prevalence of two really nasty brain cancers: astrocytomas and gliomas. This got international attention. In the US we didn't see any big problem in consumer products but the EEC/EU took it very seriously indeed. Regulations were passed to keep EMF down to very low levels. Me? I often found myself working in high voltage substations where just touching a grounded fence produced an unpleasant shock. I hoped I would get cool mutations, like wings, but it never happened. Sometime in the last decade or two - I noticed it at the time but then forgot just when it was - a much larger study showed no correlation between EMFs and cancers. That is where we stand now; EMFs are a technical problem rather than a health problem. However, during the time when EMFs had everybody's attention I saw a lot of tests for EMF levels and for radio equipment (like amateur radio transmitters) being affected by the car, and the car being affected by the equipment. Nothing ever showed up. Technically speaking, there are good reasons for not even seeing large EMFs inside electric or hybrid cars. Much of the HV wiring is DC, and the AC wiring is on the other side of the firewall and floor pan from the passengers. In effect, an EMF shield is inherent in modern electric/hybrid automotive design.
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  2. The hybrids don't work without them. Seriously, though I was talking about the reliability of the 2002 Prius I had bought with 102K miles on it and put another 100K miles on it before I retired and gave him the car I no longer needed. Where was I? Oh - at 210K miles we rebuilt the NiMH hybrid battery. It was the second actual repair we had ever done to the car. It needed an inverter coolant pump at 190K miles, tires, wiper blades, routine maintenance and that's all. We reflected how it was true that there are a lot more things to fail, but they don't often fail! After 19 years the interior is in terrific shape, the car does what cars are supposed to do, and it has never stranded any of us. Quite complex and very reliable. The bottom line is that since we bought our first 2002 Prius we have never even looked at anything else. The reliability is far beyond that of any car we have had in our 46 years together. Don't fear the hybrid battery.
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  3. I don't know about nickel, but lithium has been in the news occasionally as a potential conflict mineral in South America. The lithium deposits apparently span several countries and, like oil, can be mined under foreign soil be slant drilling. (Lithium is mined by injecting water into deposits and bringing up the mineral in solution.)
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  4. Toyotas also have a hybrid battery cooling system. That is the one that has the filter the CCN told us about.
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  5.  @gnawty4662  You're welcome! Those first years in the electric company with the possibility of a higher rate of brain cancers were spooky, though.
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  6.  @bogdanmongol9518  Getting OT now... I recently saw a video saying Teslas have more of a problem with that than Toyotas do. They also have a 12V aux battery to boot it and access is no fun at all.
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  7. https://batteryuniversity.com/learn/article/charging_nickel_metal_hydride says: "The charge efficiency of nickel-based is close to 100 percent up to 70 percent charge. The pack remains cool but it begins to warm up with decreased efficiency towards full charge." That makes sense to me. IIRC Toyota uses only a conservative fraction of the battery capacity, keeping it well away from complete charge or discharge. I would think the NiMH battery pack would get very warm and overtax the cooling if the efficiency were low.
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  8.  @TaaviTuisk  I didn't either until I found that. It probably explains why NiMH is not so great for plug-in hybrids, where maximum charge is nice.
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  9. I've removed and installed a NiMH battery the low tech way. I got to thinking I should have rented an engine hoist.
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  10. I rebuilt the NiMH battery in the 2002 Prius I bought in 2004 and gave to my son when I retired. The rebuild kit came from a place in southern California; there was a $400 core charge for the modules. That makes me think they are recycled. BTW, the car had about 201K miles on it in 19 years. If anybody does this on a first gen battery that underwent the sealant process, you will find it largely glued together with a brown cement. That can be softened with an oily solvent... I had Techron handy and it worked. Paint on, let sit a minute, score with a knife, repeat for an hour or two. Patience is critical.
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  11. In fact, Ni-Cd is the only one that does. It has something to do with a 10% or so difference in anode and cathode efficiency.
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  12. Cell phone makers are recommending the same: don't keep it on a charger and avoid fully charging on a regular basis. Apparently the batteries don't like it.
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